Oksana Arrives in Court with New Lawyer

9/17/2010 12:30 PM PDT

Oksana Arrives in Court with New Lawyer

Oksana Grigorieva just arrived at the courthouse with her new lawyer, Sorrell Trope.

Our sources say Trope just filed substitution of attorney documents -- which officially makes Trope Oksana's lawyer in her custody war with Mel Gibson.

We're told one of the issues before the court today -- whether Mel's landscaper can be deposed in the family law case.  As we already reported, on February 18 -- the day Oksana secretly taped Mel -- the two of them participated in a ceremony to place their daughter Lucia's placenta around a tree.

Mel allegedly felt Oksana had been flirting with the landscaper ... which then caused a big scene.